The race for the white house, now. It's "your voice, your vote," just 35 days before the final vote. And president obama and mitt romney, one day away from that first and crucial debate. Both candidates cramming in private. Stakes could not be higher for romney behind, now, in the battleground states. Jake tapper is in las vegas, where the president has set up debate camp. Good morning, jake. Reporter: Good morning, george. That's right, both campaigns have been intensity particip participating in mock debates. President obama working on keeping his answers concise. Mitt romney trying to get used to the one-on-one format. In a race this close, both candidates know anything could make the difference tomorrow night. Mitt romney held a rally in denver overnight, where he previewed tomorrow night's fireworks. These debates are an opportunity for each of us to describe the pathway forward for america that we would choose. And the american people have to make their choice as to what kind of america they want. Reporter: He will likely start the day tomorrow with a workout. He's an elliptical machine kind of guy. The president is at this posh resort in nevada, where he'll, no doubt, be hitting the gym before another day of debate practice. While he may be strong physically, he admits he's out of debate shape. Romney debated most recently in february. I think the earmarks, we had it with them. Reporter: The last time the president debated was almost four years ago. We need a president who is going to tackle it head-on. Reporter: It's not clear how much this is lowering expectations. But sources tell abc news, that the president's debate prep has been exhausting and he's clearly out of practice. Something he talked about working the phones at this campaign office. They're keeping me indoors all the time. They're making me do my homework. Reporter: George, in the latest quinnipiac poll, president obama leads mitt romney, helping the president in that number, an 18-point lead among women voters. Romney leads among men voters by ten points. That could be the difference in this election. The trash-talking among candidates is getting comical among campaign staff. What is the obama team expecting from romney tomorrow night? A candidate on attack? Reporter: In key moments, when romney needs to attack, he has, to dispatch newt gingrich or rick parry. They are planning for that tomorrow night. We'll have the debates tomorrow night at 9:00 eastern,

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